Pyranodipyran Derivatives with Tyrosyl DNA Phosphodiesterase 1 Inhibitory Activities and Fluorescent Properties from Aspergillus sp. EGF 15-0-3.

Four new benzodipyran racemates, namely (±)-aspergiletals A-D (3-6), representing a rare pyrano[4,3-h]chromene scaffold were isolated together with eurotiumide G (1) and eurotiumide F (2) from the soft-coral-derived fungus Aspergillus sp. EGF 15-0-3. All the corresponding optically pure enantiomers were successfully separated by a chiral HPLC column. The structures and configurations of all the compounds were elucidated based on the combination of NMR and HRESIMS data, chiral separation, single-crystal X-ray diffraction, quantum chemical 13C NMR, and electronic circular dichroism calculations. Meanwhile, the structure of eurotiumide G was also revised. The TDP1 inhibitor activities and photophysical properties of the obtained compounds were evaluated. In the TDP1 inhibition assay, as a result of synergy between (+)-6 and (-)-6, (±)-6 displayed strong inhibitory activity to TDP1 with IC50 values of 6.50 ± 0.73 µM. All compounds had a large Stokes shift and could be utilized for elucidating the mode of bioactivities by fluorescence imaging.

Prospects and Problems for Identification of Poisonous Plants in China using DNA Barcodes.

OBJECTIVE: Poisonous plants are a deadly threat to public health in China. The traditional clinical diagnosis of the toxic plants is inefficient, fallible, and dependent upon experts. In this study, we tested the performance of DNA barcodes for identification of the most threatening poisonous plants in China. METHODS: Seventy-four accessions of 27 toxic plant species in 22 genera and 17 families were sampled and three DNA barcodes (matK, rbcL, and ITS) were amplified, sequenced and tested. Three methods, Blast, pairwise global alignment (PWG) distance, and Tree-Building were tested for discrimination power. RESULTS: The primer universality of all the three markers was high. Except in the case of ITS for Hemerocallis minor, the three barcodes were successfully generated from all the selected species. Among the three methods applied, Blast showed the lowest discrimination rate, whereas PWG Distance and Tree-Building methods were equally effective. The ITS barcode showed highest discrimination rates using the PWG Distance and Tree-Building methods. When the barcodes were combined, discrimination rates were increased for the Blast method. CONCLUSION: DNA barcoding technique provides us a fast tool for clinical identification of poisonous plants in China. We suggest matK, rbcL, ITS used in combination as DNA barcodes for authentication of poisonous plants.

[Determination of serum carbamazepine concentration and metabonomic analysis in rats].

OBJECTIVE: To study the effects of carbamazepine on serum metabolic profiles in rats using nuclear magnetic resonance (NMR) spectroscopy. METHODS: Twenty-four healthy male Wistar rats were randomized into 4 groups (n=6) for daily intragastric administration of high-, medium- or low-dose carbamazepine or distilled water (control) for 7 days. Blood samples were collected from the abdominal aortic under anesthesia after the treatment to determine serum carbamazepine concentration using high-performance liquid chromatography. ¹H nuclear magnetic resonance (¹H NMR) spectra were acquired for pattern recognition analysis. Histopathological changes of the renal and liver tissues of the rats were also examined. RESULTS: Steady-state blood concentration of carbamazepine in high-, medium- and low-dose groups were 14.64 ± 1.41, 8.54 ± 1.19, and 4.56 ± 0.64 µg/ml, respectively. Slight liver swelling was found in high-dose group, but none of the groups showed renal pathologies. Compared with the control group, the high-dose carbamazepine group showed lowered serum concentrations of 1,3-diaminopropane, deoxycorticosterone, 7-dehydrocholesterol, betaine, beta-alanine, L-cystathionine, 4-methyl-2-oxovaleric acid, and creatine with increased levels of saccharides, lactate, succinic acid, acetyl phosphate, and adipic acid. Principal component analysis revealed significant differences of the metabolites between carbamazepine-treated groups and the control group. The metabolic profiles showed no differences in the kinds of metabolites although the concentrations of the metabolites varied between the carbamazepine groups. CONCLUSIONS: Carbamazepine significantly affects metabolism in normal rats. This finding provides evidence for clinical drug monitoring and drug safety of carbamazepine. NMR technique has important values for pharmacodynamic and toxicological evaluation of drugs.

Pelopuradazole, a new imidazole derivative alkaloid from the marine bacteria Pelomonas puraquae sp. nov.

One new imidazole derivative alkaloid pelopuradazole (1), together with three known alkaloids as in 3H-imidazole-4-carboxylic acid (2), 1H-pyrrole-2-carboxylic acid (3) and 2-methyl-3H-imidazole-4-carboxylic acid (4) and two known cyclo-dipeptides pelopurin A (5) and pelopurin B (6), has been isolated from the marine bacterium Pelomonas puraquae sp. nov. Pelopuradazole (1) was a new imidazole derivative alkaloid, while compounds 2, 3, 5 and 6 were firstly obtained as natural products. Compounds 1-6 were isolated from P. puraquae sp. nov. for the first time.

Antiproliferative triterpenoid saponins from the stem of Psychotria sp.

Six new triterpenoid saponins, psychotrianosides A-F (1-6), and two known triterpenoid saponins, psychotrianoside G (7) and ardisianoside D (8), were isolated from Psychotria sp. Their structures were determined mainly by spectroscopic methods. The cytotoxic activities of 1-8 against five human cancer cell lines (MDA-MB-231, MCF-7, MCF-7/ADM, HepG2, and HepG2/ADM) are reported for the first time. Psychotrianoside C (3) showed the most potent antiproliferative activity among these saponins, and the IC50 value of 3 against MDA-MB-231 was 2.391 ± 0.161 µM. Compound 3 was also found to induce apoptosis.

New sphingolipid psychotramide A-D from the stem of Psychotria sp.

Chemical study of the Psychotria sp. led to the isolation of a new type of ceramide named psychotramide (1). HR-FAB-MS analysis revealed that psychotramide consists of four new sphingolipids. Their structures were determined on the basis of the spectroscopic data and chemical methods to be psychotramide A (1-a), psychotramide B (1-b), psychotramide C (1-c) and psychotramide D (1-d).